Footrest mechanism, chair support structure and chair having same

ABSTRACT

The present disclosure provides a footrest mechanism, a chair support structure and a chair. The footrest mechanism comprises a first support component, a first folding arm, a first rotating member and a first leg connecting rod, which can define a first four-bar mechanism. The first leg connecting rod is connected to the chair component, and is pivotally connected to the first rotating member. The first folding arm is pivotally connected to the first rotating member and the first support component, respectively. The first support component is pivotally connected to the first leg connecting rod. The first leg connecting rod is capable of moving towards or away from the chair component, and rotating relative to the first rotating member. The first leg connecting rod has a first state and a second state.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims all benefits accruing under 35 U.S.C. § 119 fromChina Patent Application No. 202022128862.6, filed on Sep. 24, 2020,titled “FOOTREST MECHANISM, CHAIR SUPPORT STRUCTURE AND CHAIR HAVINGSAME” in the China National Intellectual Property Administration, thecontent of which is hereby incorporated by reference.

TECHNICAL FIELD

The present disclosure relates to chairs, in particular to a footrestmechanism, a chair support structure and a chair having the same.

BACKGROUND

Currently, a chair having a movable footrest can include a chair supportstructure for supporting a user and a footrest mechanism rotatablyconnected to the chair support structure. The footrest mechanism can bepivotally connected to the chair support structure via a leg connectingrod. The footrest mechanism can be controlled by the user to extend fromunder the chair support structure, so as to define a footrest forsupporting legs and feet of the user, and facilitating a restfulposition for the user. The extended footrest mechanism can also becontrolled by the user to collapse and accommodate under the chairsupport structure, so that the user can get up off the chaircomfortably.

In order to increase the support area of the footrest mechanism to theuser's legs and feet, the size of the conventional footrest mechanism isrelatively large, which not only increases the weight of the footrestmechanism, but also makes the structure of the footrest mechanism to beinsufficiently compact. When the footrest mechanism is in a contractedstate, the footrest support component and the leg connecting rod cannotbe folded well, and may even protrude outward relative to the entirechair. The foot support is not only vulnerable to external collisions,but also causes inconvenience to the transportation and transfer of thechair. In addition, the footrest support component may contaminate theclothes of the user, which affects the chair experience.

SUMMARY

It is necessary to provide an improved footrest mechanism, a chairsupport structure and a chair having the same.

The present disclosure provides a footrest mechanism, including a firstsupport component, a first folding arm, a first rotating member and afirst leg connecting rod. The first leg connecting rod is connected tothe chair component, and is pivotally connected to the first rotatingmember. The first folding arm is pivotally connected to the firstrotating member and the first support component, respectively. The firstsupport component is pivotally connected to the first leg connectingrod. A first leg four-bar mechanism is defined by the first supportcomponent, the first folding arm, the first rotating member and thefirst leg connecting rod. The first leg connecting rod is capable ofmoving towards or away from the chair component, and rotating relativeto the first rotating member, so as to drive the first leg four-barmechanism to contract or expand. The first leg four-bar mechanism has afirst state and a second state. When the first leg four-bar mechanism isin the first state, the first folding arm is close to the first rotatingmember, the first leg connecting rod is configured for driving the firstsupport component to move close to the first rotating member, and thefirst leg four-bar mechanism is folded. When the first leg four-barmechanism is in the second state, the first folding arm is away from thefirst rotating member, and the first leg connecting rod is configuredfor driving the first support component to move away from the firstrotating member, and the first leg four-bar mechanism is expanded.

Furthermore, when the first leg four-bar mechanism is in the secondstate, the first leg four-bar mechanism is in a concave quadrilateralshape.

Therefore, when the first leg four-bar mechanism is adjusted from thefirst state to the second state, a dead point of the motion mechanismbetween the first support component and the first leg connecting rod canbe avoided. Thus, the deformation of the first leg four-bar mechanismfrom the first state to the second state is smooth with low resistance.This reduces an extrusion force and abrasion of the pivot point betweenthe first support component and the first leg connecting rod.

Furthermore, the first leg four-bar mechanism includes a first limitingelement. When the first leg four-bar mechanism is in the first state,the first limiting element is configured for limiting at least one ofthe first rotating member, the first folding arm, the first supportcomponent and the first leg connecting rod, and limiting a folding rangeof the first leg four-bar mechanism.

Therefore, the first limiting element can facilitate avoiding theinterference of elements collision or extrusion caused by unduly foldingand contracting of the first leg four-bar mechanism, so as to avoidmalfunctions caused by deformation of a member or overload of pivotpoints between members.

Furthermore, the first limiting element is fixed to the first rotatingmember. When the first leg four-bar mechanism is in the first state, thefirst limiting element is configured for limiting the first legconnecting rod.

Furthermore, the first leg four-bar mechanism includes a second limitingelement. When the first leg four-bar mechanism is in the second state,the second limiting element is configured for limiting at least one ofthe first rotating member, the first folding arm, the first supportcomponent and the first leg connecting rod, and limiting an expandingrange of the first leg four-bar mechanism.

Therefore, the second limiting element can avoid excessive expanding ofthe first four-bar mechanism, so as to better ensure a relative positionbetween the first support component and the first rotating member,thereby better supporting a user's legs and feet and ensuring thecomfort of the user's legs and feet.

Furthermore, the second limiting element is fixed to the first rotatingmember. When the first leg four-bar mechanism is in the second state,the second limiting element is configured for limiting the first supportcomponent.

The present disclosure further provides a chair support structure,including a movable chair mechanism and the footrest mechanism. Themovable chair mechanism includes a chair component, and the footrestmechanism is connected to the chair component.

Furthermore, the movable chair mechanism further includes anintermediate transmission component and an installation component. Theintermediate transmission component includes a first transmissionconnecting rod, a second transmission connecting rod and a thirdtransmission connecting rod. The first transmission connecting rod andthe third transmission connecting rod are pivotally connected to thechair component, respectively. Two ends of the second transmissionconnecting rod are pivotally connected to the first transmissionconnecting rod and the third transmission connecting rod, respectively.The installation component includes a fixing rod, a first swing arm anda second swing arm. The fixing rod is fixed to a base. Two ends of thefirst swing arm are pivotally connected to the first transmissionconnecting rod and the fixing rod, respectively. Two ends of the secondswing arm are pivotally connected to the third transmission connectingrod and the fixing rod, respectively. The installation component iscapable of expanding or contracting to drive the intermediatetransmission component to move. The intermediate transmission componentis capable of driving the chair component to move along a firstdirection.

Therefore, the mechanism connection between the chair component and thebase can be improved by the intermediate transmission component and theinstallation component. When the movable chair mechanism moves, thealtitudinal change of the chair component and the chair supportstructure is reduced, so that the user will not feel obviously up anddown. In addition, the height of a sitting state, a casual state and alying state of the chair component and the chair support structurethereof can be lowered, so that the gravity center of the user can belowered. This facilitates eliminating chair component sway and unstablesupport caused by excessively high gravity center of the user, andensuring balance of the chair component.

Furthermore, the chair support structure includes two sets of thefootrest mechanism and two sets of the movable chair mechanism. The twosets of the footrest mechanism and the two sets of the movable chairmechanism are capable of moving synchronously and correlatively,respectively.

Therefore, the two sets of footrest mechanism support the user's twolegs, respectively. The two sets of movable chair mechanism can supportthe user more stable, so as to increase support balance.

The present disclosure further provides a chair including the base andthe chair support structure. The movable chair mechanism is connected tothe base.

Furthermore, the chair further includes a driving component. The drivingcomponent is pivotally connected to a footrest mechanism and the chaircomponent, respectively. The driving component is capable of driving thefootrest mechanism to move towards or away from the chair component, anddriving the chair component to move along the first direction.

Therefore, the expanding and contracting of the movable chair mechanismand the footrest mechanism can be synchronously electrically driven.Furthermore, while the footrest mechanism is driven by the drivingcomponent to move towards or away from the chair component, the firstleg four-bar mechanism can be driven by the first leg connecting rod andthe first rotating member to contract or expand. That is, each componentof the footrest mechanism can simultaneously contract and expand alongwith the contraction and expansion of the chair component.

In the footrest mechanism of the present disclosure, the first supportcomponent can support the user's feet. The first rotating member cansupport the user's legs. Therefore, the first support component and thefirst rotating member work together to hold the user's legs and feet.The contact area between the footrest mechanism and the user's legs isenlarged, so that the comfort of the user's legs and feet is increased.At the same time, when the footrest mechanism is retracted relative tothe chair component, the structure of the folded footrest mechanism canbe in a smaller size, so that a space occupied by the footrest mechanismcan be reduced. The first support component can be further folded to beaccommodated at a side of the first rotating member near a back side ofthe chair. Therefore, the probability of the first support componentbeing impacted by the outside can be reduced, and it can be also moreconvenient for the user to transfer or carry the chair, and prevent thefirst support component from contaminating the user's clothes. The usercan have a better use experience of the chair.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a structural schematic view of a chair in a sitting state inone embodiment of the present disclosure.

FIG. 2 is a structural schematic view of a chair in a casual state inone embodiment of the present disclosure.

FIG. 3 is a structural schematic view of a chair in a lying state in oneembodiment of the present disclosure.

FIG. 4 is a side view of the chair of FIG. 1 in the sitting state.

FIG. 5 is a side view of the chair of FIG. 2 in the casual state.

FIG. 6 is a side view of the chair of FIG. 3 in the lying state.

FIG. 7 is a schematic view of a first leg four-bar mechanism in a secondstate in one embodiment of the present disclosure.

FIG. 8 is a schematic view of a first leg four-bar mechanism in a firststate in one embodiment of the present disclosure.

100 represents a footrest mechanism; 10 represents a first supportcomponent; 20 represents a first folding arm; 30 represents a firstrotating member; 40 represents a first leg connecting rod; 50 representsa second leg connecting rod; 60 represents a third leg connecting rod;70 represents a fourth leg connecting rod; 81 represents a supplementalsupport element; 811 represents a supplemental support portion; 82represents a second folding arm; 300 represents a chair; 101 representsa fixing and connecting rod; 102 represents a first swing arm; 103represents a second swing arm; 104 represents a first connecting rod;201 represents a first transmission connecting rod; 202 represents asecond transmission connecting rod; 203 represents a third transmissionconnecting rod; 301 represents a first rocker; 302 represents a secondrocker; 303 represents a chair support structure; 304 represents asliding connecting rod; 401 represents a push-rod motor; 402 representsa motor housing; 403 represents a telescoping rod; and 501 represents achair transmission element.

DETAILED DESCRIPTION

The technical solutions in the embodiments of the present disclosure areclearly and completely described in the following with reference to theaccompanying drawings in the embodiments of the present disclosure. Itis obvious that the described embodiments are only a part of theembodiments, but not all of the embodiments. All other embodimentsobtained by those skilled in the art based on the embodiments of thepresent disclosure without departing from the inventive scope are thescope of the present disclosure.

All technical and scientific terms used herein have the same meaning ascommonly understood by one of ordinary skill in the art to which thisdisclosure is claimed. The terminology used in the description herein isfor the purpose of describing particular embodiments, and is notintended to limit the disclosure. The term “or/and” as used hereinincludes any and all combinations of one or more of the associatedlisted items.

FIG. 1 is a structural schematic view of a chair in a sitting state inone embodiment of the present disclosure, FIG. 2 is a structuralschematic view of a chair in a casual state in one embodiment of thepresent disclosure, FIG. 3 is a structural schematic view of a chair ina lying state in one embodiment of the present disclosure, FIG. 4 is aside view of the chair of FIG. 1 in the sitting state, FIG. 5 is a sideview of the chair of FIG. 2 in the casual state, and FIG. 6 is a sideview of the chair of FIG. 3 in the lying state.

In general, a conventional chair having a movable footrest includes achair support structure for supporting a user and a footrest mechanismrotatably connected to the chair support structure. When the user sitsor lies on this kind of chair, the footrest mechanism can be controlledby the user to extend out from the chair support structure, so as todefine a footrest for supporting legs and feet of the user, facilitatingrest of the user. When the user wants to leave, the extended footrestmechanism can also be controlled by the user to collapse and accommodateunder the chair support structure, so that the chair can be arrangedtidily and occupy a smaller space.

The conventional footrest mechanism mainly includes a leg connecting rodpivotally connected to the chair support structure, and a footrestsupport component pivotally connected to the leg connecting rod.Specifically, the leg connecting rod can rotate relative to the entirechair support structure, so that the footrest mechanism can expand orcontract relative to the entire chair support structure. That is, theleg connecting rod not only can rotate a preset position to support theuser's legs, but also can be folded and retracted relative to the chairsupport structure to reduce the space occupied by the chair. Thefootrest support component rotates relative to the leg connecting rod.The footrest support component not only can be expanded along with theexpansion of the leg connecting rod to further enlarge the support areafor supporting the user's legs and feet, but also can be folded alongwith the retraction of the leg connecting rod to avoid malfunctions suchas jams caused by accidental collisions.

In the present disclosure, when the user lies on the chair, thedirection that the user's legs extend is defined as the front of thechair, and the direction opposite to the front of the chair is definedas the back of the chair.

In order to increase a support area of the footrest mechanism to theuser's legs and feet, the size of the conventional footrest mechanism isrelatively large, which not only increases the weight of the footrestmechanism, but also makes the structure of the footrest mechanism to beinsufficiently compact. When the footrest mechanism is folded andretracted, the footrest support component and the leg connecting rodcannot be folded well, and may even protrude outward relative to theentire chair. Therefore, the foot support is not only vulnerable toexternal collisions, but also causes inconvenience to the transportationand transfer of the chair. In addition, the footrest support componentmay contaminate the user's clothes, which affects the user's experience.

The present disclosure provides a footrest mechanism 100, a chairsupport structure and a chair 300. The chair 300 can include the chairsupport structure and a base. The chair support structure can includethe footrest mechanism 100 and a movable chair mechanism. The movablechair mechanism can include a chair component for connecting thefootrest mechanism 100.

The present disclosure provides a footrest mechanism 100, which caninclude a first support component 10, a first folding arm 20, a firstrotating member 30 and a first leg connecting rod 40. The first supportcomponent 10 can be pivotally connected to the first leg connecting rod40 to support the user's feet. The first folding arm 20 can be pivotallyconnected to the first rotating member 30 and the first supportcomponent 10, respectively. The first folding arm 20 can rotate relativeto the first rotating member 30, so that the first folding arm 20 canmove towards or away from the first rotating member 30. The firstrotating member 30 can be pivotally connected to the first legconnecting rod 40 to support the user's legs. A first leg four-barmechanism can be defined by the first support component 10, the firstfolding arm 20, the first rotating member 30 and the first legconnecting rod 40.

FIG. 7 is a schematic view of a first leg four-bar mechanism in thesecond state in one embodiment of the present disclosure, and FIG. 8 isa schematic view of a first leg four-bar mechanism in the first state inone embodiment of the present disclosure.

In FIG. 7 and FIG. 8, “A” represents a pivot point of the first rotatingarm 20 and the first rotating member 30, “B” represents a pivot point ofthe first support component 10 and the first folding arm 20, “C”represents a pivot point of the first support component 10 and the firstleg connecting rod 40, and “D” represents a pivot point of the first legconnecting rod 40 and the first rotating member 30. The first legconnecting rod 40 can be connected to the chair component, move towardsor away from the chair component, and rotate relative to the firstrotating member 30 to drive the first leg four-bar mechanism to contractor expand. The first leg four-bar mechanism can have a first state and asecond state. When the first leg four-bar mechanism is in the firststate, the first folding arm 20 can be close to the first rotatingmember 30, and the first leg connecting rod 40 can drive the firstsupport component 10 to move towards the first rotating member 30. Anacute angle can be defined by a straight line defined by “A” and “D” anda straight line defined by “A” and “B”, and the first leg four-barmechanism can be folded. When the first leg four-bar mechanism is in thesecond state, the first folding arm 20 can be away from the firstrotating member 30, and the first leg connecting rod 40 can drive thefirst support component 10 to move away from the first rotating member30. An obtuse angle can be defined by the straight defined by “A” and“D” and the straight line defined by “A” and “B”, and the first legfour-bar mechanism can be expanded.

It should be noted that in the present disclosure, the first legconnecting rod 40 can be directly connected to the chair component, orindirectly connected to the chair component via other leg connectingrods. Furthermore, in other embodiments of the present disclosure, thefootrest mechanism 100 may include other leg connect rods, but is notlimited to the first leg connect rod 40; and the first rotating member30 can be connected to the chair component via other leg connectingrods.

Specifically, in an embodiment of the present disclosure (which is namedthe present disclosure for short hereinafter), the footrest mechanism100 can further include a second leg connecting rod 50, a third legconnecting rod 60 and a fourth leg connecting rod 70. A first end of thesecond leg connecting rod 50 can be pivotally connected to a firstrotating member 30, and a second end of the second leg connecting rod 50can be pivotally connected to a first end of the fourth leg connectingrod 70. A first end of the first leg connecting rod 40 away from thefirst support component 10 can be pivotally connected to the third legconnecting rod 60. A second end of the fourth leg connecting rod 70 awayfrom the second leg connecting rod 50 can be pivotally connected to thechair component. A second end of the third leg connecting rod 60 awayfrom the first leg connecting rod 40 can be pivotally connected to chaircomponent. Furthermore, the second leg connecting rod 50 and the thirdleg connecting rod 60 can be pivotally connected to each other anddefine a cross.

A second leg four-bar mechanism can be defined by the first rotatingmember 30, the first leg connecting rod 40, the second leg connectingrod 50 and the third leg connecting rod 60. A third leg four-barmechanism can be defined by the second leg connecting rod 50, the thirdleg connecting rod 60, the fourth leg connecting rod 70 and the chaircomponent. The third leg four-bar mechanism can be driven by an energysource, which is disposed out of the footrest mechanism 100, to deform,so as to drive the second leg four-bar mechanism to deform. Therefore,the first rotating member 30 can be driven by the first leg connect rod40 to rotate relative to the second leg connecting rod 50, so that theentire first leg four-bar mechanism can expand and contract relative tothe second leg connecting rod 50. When the first leg four-bar mechanismis in a first state, the first rotating member 30 can be close to thesecond leg connecting rod 50, the first four-bar mechanism can be closeto the second leg connecting rod 50, and the footrest mechanism 100 canbe folded and accommodated from under the chair component. When thefirst leg four-bar mechanism is in a second state, the first rotatingmember 30 can be away from the second leg connecting rod 50, and theentire first leg four-bar mechanism can be away from the second legconnecting rod 50, and the entire footrest mechanism 100 can be fullyexpanded.

The present embodiment is a preferred embodiment of the presentdisclosure, and will be described in detail hereinafter. Expandedtechnical solutions of the present embodiment or simplified technicalsolutions of the present embodiment will not be described in detailshereinafter.

In the footrest mechanism 100 of the present disclosure, the firstsupport component 10 can support the user's feet. The first rotatingmember 30 can support the user's legs. Therefore, the first supportcomponent 10 and the first rotating member 30 can work together to holdthe user's legs and feet. The contact area between the footrestmechanism 100 and the user's legs can be enlarged, so that the comfortof the user's legs and feet can be increased. At the same time, when thefootrest mechanism 100 is retracted relative to the chair component, thestructure of the folded footrest mechanism 100 can be more compact, sothat a space occupied by the footrest mechanism 100 can be reduced. Thefirst support component 10 can be further folded to be accommodated at aside of the first rotating member 30 near the back side of the chair300. Therefore, the probability of the first support component 10 beingimpacted by the outside can be reduced, and it can be also moreconvenient for the user to transfer or carry the chair 300, and canprevent the first support component 10 from contaminating the user'sclothes. The user can have a better use experience of the chair 300.

Referring to FIG. 7, when the first leg four-bar mechanism is in thesecond state, the first leg four-bar mechanism can be in a concavequadrilateral shape. That is, in the second state, a concavequadrilateral shape can be defined by the straight defined by A and B,the straight defined by A and D, the straight defined by C and B and thestraight defined by C and D.

Therefore, when the first leg four-bar mechanism is adjusted from thefirst state to the second state, a dead point of the motion mechanismbetween the first support component 10 and the first leg connecting rod40 can be avoided. Thus, the deformation of the first leg four-barmechanism from the first state shown in FIG. 8 to the second state shownin FIG. 7 can be smooth with low resistance. This can reduce anextrusion force and abrasion of the pivot point between the firstsupport component 10 and the first leg connecting rod 40.

Furthermore, the first leg four-bar mechanism can include a firstlimiting element. The first limiting element can be fixed to at leastone of the first rotating member 30, the first folding arm 20, the firstsupport component 10 and the first leg connecting rod 40. When the firstleg four-bar mechanism is in the first state, the first limiting elementcan be configured for limiting at least one of the first rotating member30, the first folding arm 20, the first support component 10 and thefirst leg connecting rod 40, which is not provided with the firstlimiting element, and limiting a folding range of the first leg four-barmechanism.

Therefore, the first limiting element can facilitate avoiding theinterference of collision or extrusion caused by unduly fold andcontract of the first leg four-bar mechanism, so as to avoidmalfunctions caused by deformation of a member or overload of pivotpoints between members.

Specifically, the first limiting member can be fixed to the firstrotating member 30. When the first leg four-bar mechanism is in thefirst state, the first limiting element can be configured for limitingthe first leg connecting rod 40.

Therefore, the first limiting element can facilitate avoiding theinterference of elements collision or extrusion caused by unduly foldand contract of the first leg four-bar mechanism, so as to avoidmalfunctions caused by deformation of a member or overload of pivotpoints between members.

Furthermore, a first leg four-bar mechanism can further include a secondlimiting element. The second limiting element can be fixed to at leastone of the first rotating member 30, the first folding arm 20, the firstsupport component 10 and the first leg connecting rod 40. When the firstleg four-bar mechanism is in the second state, the second limitingelement can be configured for limiting at least one of the firstrotating member 30, the first folding arm 20, the first supportcomponent 10 and the first leg connecting rod 40, which is not providedwith the second limiting element, and limiting an expanding range of thefirst leg four-bar mechanism.

Specifically, the second limiting member can be fixed to the firstrotating member 30. When the first leg four-bar mechanism is in thesecond state, the second limiting element can be configured for limitingthe first support component 10.

Therefore, the second limiting element can avoid excessive expanding ofthe first four-bar mechanism, so as to better ensure a relative positionbetween the first support component 10 and the first rotating member 30,thereby better supporting a user's legs and feet and ensuring thecomfort of the user's legs and feet.

Furthermore, in the present embodiment, the footrest mechanism 100 canfurther include a supplemental support component. The supplementalsupport component can be pivotally connected to the first leg connectingrod 40 and the second leg connecting rod 50, respectively. Specifically,the supplemental support component can include a supplemental supportelement 81 and a second folding arm 82. The supplemental support element81 can be pivotally connected to the second folding arm 82. One end ofthe second folding arm 82 can be pivotally connected to the first legconnecting rod 40. One end of the supplemental support element 81 can bepivotally connected to the second leg connecting rod 50. Thesupplemental support element 81 can be provided with a supplementalsupport portion 811.

The supplemental support component can be configured for furtherenlarging the support area of the footrest mechanism 100 to the user'slegs, so as to improve the user's comfort when the chair 300 is in thelying state. When the first leg four-bar mechanism is in the firststate, the supplemental support component can be folded and retractedrelative to the first rotating member 30, and accommodated at the sideof the first rotating member 30 near the back side of the chair 300.When the first leg four-bar mechanism is in the second state, thesupplemental support component can be expanded relative to the first legconnecting rod 40 and the second leg connecting rod 50. The supplementalsupport portion 811, the first rotating member 30 and the first supportcomponent 10 are at the same altitude.

In other embodiments, the supplemental support element and the secondfolding arm may be integrated.

Furthermore, in the chair support structure of the present disclosure,the movable chair mechanism further can include an intermediatetransmission component and an installation component. The intermediatetransmission component can be actively connected to the chair componentand the installation component. The intermediate transmission componentcan include a first transmission connecting rod 201, a secondtransmission connecting rod 202 and a third transmission connecting rod203. The first transmission connecting rod 201 and the thirdtransmission connecting rod 203 can be pivotally connected to the chaircomponent, respectively. Two ends of the second transmission connectingrod 202 can be pivotally connected to the first transmission connectingrod 201 and the third transmission connecting rod 203, respectively.

Specifically, in the present embodiment, the chair component can includea chair support structure 303, a sliding connecting rod 304, a firstrocker 301 and a second rocker 302. The chair support structure 303 canbe configured for accommodating the user and can move relative to achair base (not shown in the figures). The sliding connecting rod 304can be configured for connecting the chair base, and pivotally connectedto the first rocker 301 and the second rocker 302, respectively. An endof the first rocker 301 away from the sliding connecting rod 304 can bepivotally connected to the chair support structure 303. An end of thesecond rocker 302 away from the sliding connecting rod 304 can bepivotally connected to the chair support structure 303. A first four-barmechanism can be defined by the chair support structure 303, the firstrocker 301, the second rocker 302 and the sliding connecting rod 304. Inthe first four-bar mechanism, the first rocker 301 and the second 302can swing relative to the sliding connecting rod 304, to define a traceof the expansion and contraction, and drive the chair support structure303 to move.

In some embodiments, the extended chair support structure can have alength in a range of 450 mm to 580 mm. Accordingly, a distance between apivot point of the chair support structure 303 and the first rocker 301and a pivot point of the chair support structure 303 and the secondrocker 302 can be in a range of 350 mm to 370 mm

The chair support structure 303 of the present disclosure can be usedfor a chair which is mainly used in the sitting state or the casualstate. The chair component and the chair support structure can have alighter weight, and the structure of the chair is light and handy. Thus,the chair support structure 303 may also be a component of a normalcasual chair.

In other embodiments, the chair support structure may have a largersize. Specifically, the extended chair support structure can have alength in a range of 580 mm to 700 mm. Accordingly, the distance betweenthe pivot point of the chair support structure and the first rocker andthe pivot point of the chair support structure and the second rocker canbe in a range of 370 mm to 450 mm.

In these embodiments, the distance between the pivot point of the chairsupport structure and the first rocker and the pivot point of the chairsupport structure and the second rocker can be enlarged, so that chairsupport structure can have a larger length. The chair support structurecan be used in a chair which is mainly used in the sitting state or thecasual state. The first rocker and the second rocker swing relative tothe sliding connecting rod, and the influence on the gravity center ofthe chair support chair structure can be further reduced. Furthermore,the height of gravity center of the chair support structure can befurther decreased without changing the structure and connection of thefirst rocker, the second rocker and the sliding connecting rod.Therefore, when the chair is in the casual state and the lying state,the balance of the user can be ensured. Thus, the chair structure can beused as a component of a chair for a deep rest. A lifting height of theseat can be lowered accordingly to better accommodate the user.

Specifically, the lifting height of the seat in one embodiment can belowered in a range of 145 mm to 160 mm.

An end of the chair support structure 303 near the user's feet can bepivotally connected to the third leg connecting rod 60 and the fourthleg connecting rod 70, respectively. The third leg connecting rod 60 andthe fourth leg connecting rod 70 can be driven by an external energysource, to drive the entire footrest mechanism 100 to expand or contractrelative to the chair support structure 303. The external energy sourcecan by a driving force from the user, or can be given an independentelectrical driving component disposed in the chair 300.

The installation component can include a fixing rod 101, a first swingarm 102 and a second swing arm 103. The fixing rod 101 is fixed to thebase. Two ends of the first swing arm 102 can be pivotally connected tothe first transmission connecting rod 201 and the fixing rod 101. Twoends of the second swing arm 103 can be pivotally connected to the thirdtransmission connection rod 203 and the fixing rod 101, respectively.

In the present embodiment, the first swing arm 102 and the second swingarm 103 can swing relative to the fixing rod 101. Therefore,installation component can drive the second transmission connection rod202 to move, so as to drive the entire intermediate transmissioncomponent to move. In addition, the first transmission connecting rod201 and the third transmission connecting rod 203 can move relative tothe second transmission connection rod 202, so that the intermediatetransmission mechanism can drive the sliding connecting rod 304 to move,thereby the sliding connecting rod 304 can drive the entire chaircomponent to move along a first direction.

Referring to FIG. 6, the first direction is a direction parallel to thefixing rod 101 and towards the user's feet, i.e., the direction of thearrow in FIG. 6. The chair support structure 303 can move along adirection parallel to or substantially parallel to the fixing rod 101.When the user sits on the chair 300, the chair support structure 303 canprotrude along the first direction. After the user uses the chair 300,the chair support structure 303 can retract along a direction oppositeto the first direction.

The movable chair component can be driven by an external energy source,so that the chair 300 can be gradually expanded from the sitting stateto the casual state or the lying state.

Furthermore, in the present embodiment, the installation component canfurther include a first connecting rod 104. An end of the firstconnecting rod 104 can be pivotally connected to the second swing arm103, and the other end of the first connecting rod 104 can be pivotallyconnected to the second transmission connecting rod 202. Specifically,the second swing arm 103 can be located near the back side of the chair300, and the first swing arm 102 can be located near the front side ofthe chair 300. A second four-bar mechanism can be defined by the firstconnecting rod 104, the second transmission connecting rod 202, thesecond swing arm 103 and the third transmission connecting rod 203.Therefore, the variance of the intermediate component and theinstallation component can be smaller, which facilitates defining amoving trace of the movable chair mechanism and avoiding disordermovement of each element.

Furthermore, in the present embodiment, the chair support structure caninclude two sets of the footrest mechanism 100 and two sets of themovable chair mechanism. The two sets of the footrest mechanism and thetwo sets of the movable chair mechanism can move synchronously andcorrelatively, respectively.

Furthermore, the chair 300 in the present disclosure can further includea driving component. The driving component can be pivotally connected tothe footrest mechanism 100 and the chair component, respectively. Thedriving component 100 can drive the footrest mechanism 100 to movetowards or away from the chair component, and drive the chair componentto move along the first direction.

Specifically, in the present embodiment, the driving component can be apush-rod motor 401 pivotally connected to the base, which can include amotor housing 402 and a telescoping rod 403. The motor housing 402 canbe pivotally connected to the base via a U-shape seat. The telescopingrod 403 can be disposed in the motor housing 402, and can expand andretract relative to the motor housing 402 along an axial direction ofthe telescoping rod 403. The terminal end of the telescoping rod 403 canbe pivotally connected to a chair transmission member 501 via a U-shapeseat. One end of the chair transmission member 501 is pivotallyconnected to the fourth leg connecting rod 70, and the other end of thechair transmission member 501 can be pivotally connected to the slidingconnecting rod 304. When the push-rod motor 401 is started, thetelescoping rod 403 can be driven by the push-rod motor 401 to graduallyexpand or contract, and drive the footrest mechanism 100 to moverelative to or away from the chair component at the same time.

In the footrest mechanism 100 of the present disclosure, the firstsupport component 10 can support the user's feet. The first rotatingmember 30 can support the user's legs. Therefore, the first supportcomponent 10 and the first rotating member 30 can work together to holdthe user's legs and feet. The contact area between the footrestmechanism 100 and the user's legs can be enlarged, so that the comfortof the user's legs and feet can be increased. At the same time, when thefootrest mechanism 100 is retracted relative to the chair component, thestructure of the folded footrest mechanism 100 can be in smaller size,so that a space occupied by the footrest mechanism 100 can be reduced.The first support component 10 can be further folded to be accommodatedat a side of the first rotating member 30 near the back side of thechair 300. Therefore, the probability of the first support component 10being impacted by the outside can be reduced, and it can be also moreconvenient for the user to transfer or carry the chair 300, and canprevent the first support component 10 from contaminating the user'sclothes. The user can have a better experience with the chair 300.

The technical features of the above-described embodiments may becombined in any combination. For the sake of brevity of description, allpossible combinations of the technical features in the above embodimentsare not described. However, as long as there is no contradiction betweenthe combinations of these technical features, all should be consideredas the scope of this disclosure.

The above-described embodiments are merely illustrative of severalembodiments of the present disclosure, and the description thereof isrelatively specific and detailed, but is not to be construed as limitingthe scope of the disclosure. It should be noted that a number ofvariations and modifications may be made by those skilled in the artwithout departing from the spirit and scope of the disclosure.Therefore, the scope of the disclosure should be determined by theappended claims.

We claim:
 1. A footrest mechanism, comprising a first support component,a first folding arm, a first rotating member and a first leg connectingrod; wherein the first leg connecting rod is connected to the chaircomponent, and is pivotally connected to the first rotating member; thefirst folding arm is pivotally connected to the first rotating memberand the first support component, respectively; and the first supportcomponent is pivotally connected to the first leg connecting rod; afirst leg four-bar mechanism is defined by the first support component,the first folding arm, the first rotating member and the first legconnecting rod four-bar; the first leg connecting rod is capable ofmoving towards or away from the chair component, and rotating relativeto the first rotating member, so as to drive the first leg four-barmechanism to contract or expand; the first leg four-bar mechanism has afirst state and a second state; when the first leg four-bar mechanism isin the first state, the first folding arm is close to the first rotatingmember, the first leg connecting rod is configured for driving the firstsupport component to move close to the first rotating member, and thefirst leg four-bar mechanism is folded; and when the first leg four-barmechanism is in the second state, the first folding arm is away from thefirst rotating member, and the first leg connecting rod is configuredfor driving the first support component to move away from the firstrotating member, and the first leg four-bar mechanism is expanded. 2.The footrest mechanism of claim 1, wherein the first leg four-barmechanism is in a concave quadrilateral shape when the first legfour-bar mechanism is in the second state.
 3. The footrest mechanism ofclaim 1, wherein the first leg four-bar mechanism comprises a firstlimiting element; and when the first leg four-bar mechanism is in thefirst state, the first limiting element is configured for limiting atleast one of the first rotating member, the first folding arm, the firstsupport component and the first leg connecting rod, and limiting afolding range of the first leg four-bar mechanism.
 4. The footrestmechanism of claim 3, wherein the first limiting element is fixed to thefirst rotating member; and when the first leg four-bar mechanism is inthe first state, the first limiting element is configured for limitingthe first leg connecting rod.
 5. The footrest mechanism of claim 1,wherein the first leg four-bar mechanism comprises a second limitingelement; when the first leg four-bar mechanism is in the second state,the second limiting element is configured for limiting at least one ofthe first rotating member, the first folding arm, the first supportcomponent and the first leg connecting rod, and limiting an expandingrange of the first leg four-bar mechanism.
 6. The footrest mechanism ofclaim 5, wherein the second limiting element is fixed to the firstrotating member; and when the first leg four-bar mechanism is in thesecond state, the second limiting element is configured for limiting thefirst support component.
 7. A chair support structure, comprising amovable chair mechanism and a footrest mechanism of claim 1, wherein themovable chair mechanism comprises a chair component, and the footrestmechanism is connected to the chair component.
 8. The chair supportstructure of claim 7, wherein the movable chair mechanism furthercomprises an intermediate transmission component and an installationcomponent, wherein the intermediate transmission component comprises afirst transmission connecting rod, a second transmission connecting rodand a third transmission connecting rod; the first transmissionconnecting rod and the third transmission connecting rod are pivotallyconnected to the chair component, respectively; and two ends of thesecond transmission connecting rod are pivotally connected to the firsttransmission connecting rod and the third transmission connecting rod,respectively; the installation component comprises a fixing rod, a firstswing arm and a second swing arm; wherein the fixing rod is fixed to abase, two ends of the first swing arm are pivotally connected to thefirst transmission connecting rod and the fixing rod, respectively; twoends of the second swing arm are pivotally connected to the thirdtransmission connecting rod and the fixing rod, respectively; and theinstallation component is capable of expanding or contracting to drivethe intermediate transmission component to move, and the intermediatetransmission component is capable of driving the chair component to movealong a first direction.
 9. The chair support structure of claim 7,wherein the chair support structure comprises two sets of the footrestmechanism and two sets of the movable chair mechanism, and the two setsof the footrest mechanism and the two sets of the movable chairmechanism are capable of moving synchronously and correlatively,respectively.
 10. A chair, comprising the base and the chair supportstructure of claim 7, wherein the movable chair mechanism is connectedto the base.
 11. The chair of claim 10, wherein the chair furthercomprises a driving component, the driving component is pivotallyconnected to the footrest mechanism and the chair component,respectively; and the driving component is capable of driving thefootrest mechanism to move towards or away from the chair component, anddriving the chair component to move along the first direction.